Question

At 373 K, a gaseous reaction A -2B + C is found to be first order. Starting with A , the total pressure at the end of 10 minutes was 176 mm and after a long time when A was completely dissociated, it was 270 mm. The pressure of A at the end of 10 minutes was

Answer 1

Answer:

Correct option is

B

47 mm of Hg

A→2B+C

att=0 x 0 0

att=10 x−y 2y y

total=x−y+2y+y

=x+2y=176mm-------(i)

att=100 0 2x x

total=2x+x=270mm

⇒3x=270

⇒x=90mmofHg

put the value of A in eq

n

(i), we get

x+2y=176

⇒90+2y=176

⇒2y=86

⇒y=43mmofHg

At the end of 10 min pessure of A is x−y=90−43=47mmofHg

Option B is correct.